Describe the general significance of the cellular level of living matter in nature and for man.

A cell, having arisen once in the form of an elementary biosystem, became the basis of all further development of the organic world. The evolution of bacteria, cyanobacteria, various algae and protozoa occurred entirely due to structural, functional and biochemical transformations of the primary living cell. During this evolution, a striking variety of cell forms was achieved, however, the general plan of the cell structure did not undergo fundamental changes. In the process of evolution, based on unicellular life forms, multicellularity arose, specialization of cells arose, and cell tissues appeared.